The present invention relates generally to a constant power load bank to simulate avionics and radar loads on aircraft systems to predict and verify power system stability as a result of constant power loads.
Avionics power supplies for radar systems etc. are designed to maintain constant power, e.g. when the load current changes the voltage also changes to maintain the DC volt-ampere product at a constant value (e.g. they have negative impedance characteristics at their inputs). It has been shown that constant power loading on an aircraft power system can cause the power system to become unstable. Old simulation methods to duplicate this phenomenon include mathematical equations representing the electrical power system including the constant power loads and power system controls. These equations are theoretical and to date have not been able to accurately predict system stability or instability as a result of constant power loading.
The following United States patent is of interest.
U.S. Pat. No. 3,840,810--Fritts et al
The Fritts patent discloses a circuit including semiconductor devices to simulate the characteristic load for high frequency energy generators, such as magnetrons used in microwave oven heating apparatus.